1. Field of the Invention
This invention relates to plastic molding apparatus whereby a part can be made with an undercut or threaded section. Similar tooling has been developed but this invention is believed to provide apparatus with more positive use and which requires reduced maintenance.
2. Description of the Prior Art
An example of the prior art is Fields et al. U.S. Pat. No. 3,247,548 (1968) wherein resilient mounted molding members are used. Another prior art device provides a collapsible core by providing helically grooved operating members capable of expanding a core element by rotary movement of an innercore member. Such rotary action results in excessive stress in shear on the actuating members.